The desirability of providing the vehicle interior with interior panels and supporting structure therefor having the capability of absorbing the impact energy of an occupant during a collision has long been established. These are several of many safety devices incorporated in the interior of the vehicle including seat belts, expandable airbags, and safety engineered instrument panels. Notable in this category of safety engineered interior panels and support structures is the provision of a knee-protecting debolsters straddle the steering column and are located at a point below the steering wheel and generally on the lower portion of the instrument panel. They are designed to absorb the impact on the occupant's knee during a head-on or nearly head-on collision as a means of supplementing the intended purpose of the seat belts and/or other occupant restraining devices which may or may not be in use by the occupant at the time of the collision.
Such devices are shown in U.S. Pat. Nos. 4,320,909; 4,421,343; 4,434,999; and U.S. Pat. No. 4,893,834.
Each is designed to yield upon the occupant's knee striking the knee bolster assembly at a force lower than that which would cause permanent injury to the occupant
Still another device, one in common use in automotive and light truck design, is an energy absorption knee bolster supporting bracket in the form of a sheet metal, U-shaped channel member having opposed side walls converging at equal angles toward the base wall supporting the knee bolster pad. This structure has the advantage of eliminating the possibility of the bracket collapsing solely at the break lines in response to an offset load (a characteristic known as "match-boxing") and provides a very acceptable product
However, there is a need for a knee bolster assembly meeting all the criteria of: (1) maintaining a consistently level load curve preferably at the initial peak level; (2) responding to lateral loading as well as straight-on loading with essentially the same deformation-displacement curve characteristics; (3) avoiding column loading on the side walls of the bracket assembly upon receiving both straight-on loads and lateral loads; (4) minimizing the load on the occupant's knee, while maximizing the amount of energy-absorbed by the bracket per unit displacement; (5) eliminating "match-boxing" during collapse of the assembly; (6) eliminating the tendency of the supporting bracket to fold along a single fold line; and (7) providing the aforementioned criteria while remaining simply constructed and relatively inexpensive.